Improvement in grate-bars



J. T. MARSHALL. Furnace Grate-Bar.

Patented Jan. 24, 187].

Tfi'irzesses:

N.PETERS, PHQTO-LITHOGRAPHER. WASHINGTON. a. C.

autism am cm .JOS'EPH T. ARSHALL, or WILMINGTON," DELAWARE.

Letters Patent No. 111,223,,"aaea January24, 1871,

IMPROVEMENT lN GRATE-BARS.

The Schedule referred to in these Lettei-B'Patent and making'parl; ofthe name.

Be it known that I, JOSEPH T. MARSHALL, have invented a certain new anduseful improvement in Grate-Bars, which I velilyfbelieve was never}before known or used priorto my invention thereof.-

.The nature of my invention consists in grate-bais made and constructedforthe purpose First, of equalizing the draught by means of remov Arepresents a frame inwhich the grate-bars are 'journaled at the frontand back end, as shown at b b.

The grate-bars'are of a pentagonal form, and the sides of the pentagonare concave. The barsare put in in such manner that the edge of one barwill always be in the center of the concave of the other bar, therebythoroughly clearing eaclrother, and

allowing no refuse or ashes or clinkers to lodge and remain betweenthem, thereby obstructing the draught.

Upon the front ends of .thebars, on the outside of the frame,Iarrangethe gear or cog-wheels O 0, when, by applying a proper crank onthe square ends D D of the bars, they may be revolved partly or wholly,agitating the fire, as desired. By means of the gear- Fignre 1represents a cross-section of my improved .ing they may be operatedsimultaneously, or, if pre-'- ferred,tbe gear-wheels may be left offalternately, and the bars thus work iii-pairs.

-In case. any one of the-bars becomes worn or burnt out, itlmay beremoved and replaced by a new one,

the rest of the bars still remaining intact.

Instead of being pentagonal the bars maybe of any nnmberjof sides, thesame being concave, always insuringthe object of my invention, viz: thatthe poiut" or edge'of one bar shall come opposite to andcnt out of theconcave side of the next bar any residuum, such as cliukers,"&c., thusleaving no possible cbancefor my grate to clog, and always producing agood draught. 'Having thus" described my invention, r. What claimasn'ew, and desire to secure by-Letters Patent, is a Y K I I 1. Aseriesof revolving grate-bars, with any num-,

ber of concave sides, constructed for the"purposes.

herein shown'and setffortln I 2. The combination of theframe A with thepentagonalor 'niany-s'idedconcave bars B, geared by wheels 0 and endsD,-all constructed and arranged substantially as herein shown, andfor,the purposes set forth. o v

In testimduy whereof I have signed my name to this'specification in thepresence of two-subscribing witnesses. V

JOSEPH T. MARSHALL. Witnesses:

CHAS. G. FISHER, J A0013 W. SATTERTHWAIT.

